Sanaa , Yemen -LRB- CNN -RRB- -- Yemen 's information minister escaped an assassination attempt unharmed Tuesday , his office manager said .

The minister , Ali al-Amrani , was headed to the prime minister 's office when the attack occurred , spokesman Abdul Basit al-Qaedi told CNN .

At least 10 bullets were shot in the direction of the vehicle al-Amrani was getting into , al-Qaedi said . Three bullets hit the back window and trunk of the car , he added .

Witnesses said there were at least two gunmen .

Al-Amrani was not hurt in the attack , al-Qaedi said .

The minister 's office said al-Amrani has been targeted recently in a hate campaign by pro-revolution groups .

`` A number of factions in the country started a hate campaign against the minister and threats were given to him in the past , '' said al-Qaedi .

Yemen 's Interior Ministry told CNN the attack is under investigation , but there are no prime suspects .

Last week , al-Amrani received a death threat by an anonymous caller from a Saudi telephone number , al-Qaedi said .

The minister recently launched a massive presidential campaign to support candidate Abdurabu Hadi , the country 's current vice president .

Al-Amrani told CNN the country is facing a critical time for change and all Yemenis must stand together to support Hadi .

Yemen has been beset with demonstrations against President Ali Abdullah Saleh since early last year , when pro-democratic uprisings spread across the Arab world .

Demonstrators have continued their protests against the president , despite a power transfer deal that leads to his departure .

Under the plan , Saleh -- who 's been in office for 33 years -- will step down after the February 21 elections and will receive immunity under the plan forged by the Gulf Cooperation Council .

Executive powers have already been transferred to Hadi .

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The minister has been the target of a hate campaign , his aide says

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There were at least two gunmen , witnesses say

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Pro-democracy protests have been going on for months in Yemen